J. Nannoplankton Res. 26 (1), 2004, pp.13-45 © 2004 International Nannoplankton Association
ISSN 1210-8049 Printed by Cambridge University Press, UK

13Long-term evolution of calcareous dinoflagellate
associations since the Late Cretaceous: comparison of ahigh- and a low-latitude core from the Indian Ocean
Michael Streng
University of Uppsala, Department of Earth Sciences, Palaeobiology, Norbyvägen 22, 75236 Uppsala, Sweden; streng@uni-bremen.deTania Hildebrand-Habel
University of Oslo, Department of Geology, PO Box 1047 Blindern, 0316 Oslo, Norway

Helmut Willems
University of Bremen, FB-5 Geosciences, PO Box 330 440, 28334 Bremen, Germany

Abstract One high- and one low-latitude Ocean Drilling Program core, from the southern and eastern Indian
Ocean, respectively, was studied to obtain a general overview of the evolution of calcareous dinoflagellate cyst associations in this region and their possible reaction to known major Cenozoic climatic changes. Despite a relatively
low sample density, several shifts in calcareous dinoflagellate assemblages could be linked to periods of major climatic or environmental change, at the Cretaceous/Tertiary transition, in the Early Oligocene, and in the Neogene.
Correlations between changes in the climate and in the associations appear to be more distinctive at high latitudes
than at low latitudes. For the first time, shifts in the stratigraphic distribution patterns of different archeopyle types
have been evaluated. The ratio between small and large archeopyles turned out to be a possible tool for the reconstruction of long-term climatic evolution at high latitudes, with small archeopyles correlating with warmer periods
and large archeopyles characterising cooler conditions. Altogether, 65 taxa have been distinguished, of which several are rare or problematic taxa, which may partly represent new species. These are informally described or describedusing open nomenclature. Additionally, the relationship and potential synonymy of the problematic species
Thoracosphaera? prolata with Calciodinellum elongatum is discussed in detail.

Keywords Calcareous dinoflagellates, Cenozoic, Indian Ocean, ODP, climate change, taxonomy

1. Introduction
During the last few years, large amounts of data have been
published on the ecology of calcareous dinoflagellate
cysts (e.g. Höll et al., 1998, 1999; Vink et al., 2002) andtheir use as proxies in palaeoceanography (e.g. Esper etal., 2000; Vink et al., 2001). However, as those studies
concentrated mainly on the Quaternary, investigations ofcalcareous dinoflagellate cyst associations covering
longer time-periods within the Cenozoic are still scarceand only comprise studies by Fütterer (1977, 1984),
Hildebrand-Habel et al. (1999) and Hildebrand-Habel &Willems (2000). Especially, high-latitude assemblages arepoorly studied and still many questions need to beaddressed, e.g. how do high-latitude associations differ
from those of middle or low latitudes, do typical high-latitude associations exist, and how do high latitude assemblages of calcareous dinoflagellate cysts react to climaticchanges during the Cenozoic compared to those of lower
latitudes? Additionally, all previous studies on long-term
assemblage changes concentrated on the Atlantic Ocean.
This study is the first record of Cenozoic calcareous
dinoflagellate cyst associations of high and low latitudes
in the Indian Ocean. It supplements the results on calcare-ous dinoflagellate distributions of Fütterer (1990) and
Hildebrand-Habel & Streng (2003) from the high-latitude
eastern Weddell Sea, and of Hildebrand-Habel et al.
(1999) and Hildebrand-Habel & Willems (2000) from the
mid-latitude South Atlantic Ocean. A comprehensive
evaluation of all available information on changes in calcareous cyst associations during the Cenozoic should provide a basis for subsequent detailed and high-resolution
studies of selected stratigraphic intervals.
2. Localities and material
The studied samples originate from two cores of the
Ocean Drilling Program (ODP), Hole 747A, Kerguelen
Plateau, southern central Indian Ocean (ODP Leg 120),and Hole 761B, Wombat Plateau, eastern Indian Ocean(ODP Leg 122) (Figure 1). A single sample from ODP
Leg 120, Hole 747C (sample 120-747C-1R-4, 66-67cm)
was used to supplement the poor Oligocene recovery ofHole 747A. To avoid confusion in the following, datafrom this sample are regarded as belonging to Hole 747A.
The Kerguelen Plateau is a broad, NW-SE-directed
topographic high, located between 54˚-57˚S and 61˚84˚E, separated from the Antarctic continent by the14Streng, Hildebrand-Habel, Willems

Princess Elizabeth Trough. Site 747 (54˚48.68’S,
76˚47.64’E) is located in the central zone of the
Kerguelen Plateau, at a water-depth of about 1700m,
approximately 300km SE of Heard Island. The central
Kerguelen Plateau formed 120-110Ma ago by excessive
volcanic activity at the axis of the spreading ridge that
separated India from Antarctica (Munschy et al., 1992).
Sedimentation rates at Site 747 varied notably. They wererelatively high in the Maastrichtian (about 20m/my),whereas the Early Cenozoic evolution of the Kerguelen
Plateau is characterised by continuous sedimentation at avery low rate (less than 1m/my) and two major hiatuses(63.8-58Ma and 52.6-37.8Ma) related to recurrent faulting and subsidence, resulting in a condensed succession(Shipboard Scientific Party, 1989). The break-up of theNorth Kerguelen Plateau and the Broken Ridge in the
Middle Eocene (43-42Ma) was accompanied by a sedimentation change due to an intensification of the physicaloceanic regime (Munschy et al., 1992). With the beginning of the Late Oligocene, the sedimentation rateincreased to about 5m/my and remained constant until the
Holocene, except for a brief hiatus of 2.5Ma at the
Miocene-Pliocene boundary (Shipboard Scientific Party,1989). The samples of Hole 747A consist of creamcoloured foraminifer-diatom oozes (sections 1H-5, 2H-4,
3H-3, 4H-1 and 4H-3), white nannofossil oozes (sections
4H-6, 6H-1, 7H-4, 9H-5, 12H-2, 14H-2 and 14H-5), andwhite to pale brown nannofossil chalks (sections 1R-4,
19X-2, 20X-1 and 21X-1).
The Wombat Plateau is a small, W-E-directed elevation extending from about 16.5˚S to 17.0˚S and from
114.5˚E to 115.5˚E. It is the northern part of the Exmouth
Plateau, a large, marginal plateau off NW Australia, fromwhich it is separated by the Wombat Half-graben. The
Exmouth Plateau is part of the north-western Australianmargin and is underlain by continental crust (Exon et al.,1992). Site 761 is located in the north-eastern section of
the central part of the Wombat Plateau in a water-depth of
2189m, about 530km NW of Port Hedland (Western
Australia). The Exmouth Plateau was part of the northernshore of eastern Gondwana during the Early and Middle
Mesozoic, until Late Triassic to Late Jurassic rifting
processes caused the break-up of the northern margin.
Subsequent rapid subsidence of the plateau during theCretaceous led to a change in sedimentation: the Triassic
to Early Cretaceous detrital, terrestrially-influenced sedimentation was successively replaced by hemipelagicmarls and chalks in the mid-Cretaceous. Eupelagic sedimentation of oozes and chalks subsequently dominatedthe Cenozoic (Exon et al., 1992). Sedimentation rates ofthe studied section of Site 761 varied significantly: relatively high sedimentation rates during the uppermost
Cretaceous (20m/my) dropped drastically in the initial
Paleocene, and the Cretaceous/Tertiary (K/T) boundary
itself is represented by a slight hiatus. Until the Middle
Eocene, sedimentation had been generally of medium
rate, decreasing from 12m/my in the Lower Paleocene toa minimum of 2.5 m/my in the Eocene. After a major hiatus (Middle Eocene to upper Oligocene), Neogene sedimentation rates were generally lower, with an average of
1.5m/my, and the sedimentation was interrupted by threeminor, short hiatuses between the Pliocene and Miocene(Shipboard Scientific Party, 1990). The examined samplesof Hole 761B consist of white to light grey- or greenishgrey-coloured oozes (sections 2H-3 to 16X-2) and white
to grey chalks (sections 18X-2 to 25X-3).

Figure 1: Location of the two studied ODP sites in the eastern andsouthern Indian Ocean

3. Methods
3.1 Sample preparation
The individual samples were suspended in tap-water,
buffered with ammonia to prevent dissolution, and repeatedly frozen and thawed to achieve complete disintegration. Afterwards, the material was washed through 125µm
and 20µm sieves. The residue was dried and the fraction
between 20 and 125µm was used to pick the specimensfrom under a binocular microscope. The selected specimens were mounted on aluminium stubs, sputter-coatedwith gold, and photographed under a scanning electron
microscope (SEM; CamScan-44) at the University ofBremen.
The biostratigraphic zonation used herein is that proposed by Martini (1971) and Sissingh (1977) and is takenfrom Schlich et al. (1989) for Hole 747A and Haq et al.
(1990) for Hole 761B.
3.2 Frequency estimate
Frequencies of calcareous dinoflagellate cysts at Site 747(Figure 2) were determined as follows: about 1cm3 ofeach sample was dried, weighed and sieved as describedabove. Afterwards, the separated fractions were dried andweighed individually. The dry 20-120µm fraction was

Long-term evolution of calcareous dinoflagellate associations

homogenised and about 70µg of the dried fraction separated, weighed and transferred to a picking tray. Everyobject resembling a cyst of this microsplit was picked
under a binocular microscope, mounted on an SEM stuband studied under the SEM. With the obtained number ofcysts, and the weights of the individual fractions, the frequency of calcareous cysts in each sample (cysts per gramsediment) was calculated. Frequencies of calcareous
dinoflagellate cysts at Site 761 were estimated during
picking of the individual samples. A fixed volume of eachsample was homogeneously distributed on a picking tray
which is subdivided into 45 squares of 1cm2. The total
number of specimens of calcareous dinoflagellate cysts offour squares were counted using a binocular microscopeand classified in four categories as follows: rare = 1-20
specimens, few = 21-100 specimens, common = 101-200
specimens, and abundant = more than 200 specimens.
3.3 Distribution of archeopyle types
Eight archeopyle types of calcareous dinoflagellate cysts
are currently distinguished (Streng et al., in press),
according to the system introduced for organic-walled
dinoflagellates by Evitt (1967). These archeopyle types
are accommodated in three categories: apical, intercalary,and combination archeopyles. A fourth category holds all
taxa with an archeopyle of uncertain affinity. The taxa ofHole 747A and Hole 761B have four different archetypal
types which belong to three of the four categories: Type A(apical archeopyle), Type (3AtI), Type (3AtItP) andType(3AtItP)@) (all combination archeopyles), andarcheopyles of uncertain affinity. The calcareous dinoflagellate taxa have been categorised and plotted according
to those three categories in Figures 3 and 4. Additionally,
the combination archeopyles are separated into two subcategories: mesoepicystal and epitractal archeopyles (seeStreng et al., in press and Head, 1998 for definitions ofthese archeopyle types). Pithonelloid taxa were treatedseparately, since their affiliation with the dinoflagellates
is doubtful (Fensome et al., 1993; Streng et al., in press),
as well as Thoracosphaera heimii, since its calcareous test
is not a resting cyst (Tangen et al., 1982). Variations in therelative abundance of archeopyle types are illustrated in
Figure 6, with the relevant archeopyle types grouped asfollows: 1) small archeopyles - apical archeopyles thatinvolve a single plate (Type A); 2) large archeopyles archeopyles that involve more than one plate (Type(3AtI), Type ((3AtItP)@), and Type (3AtItP)); and 3)
unknown archeopyle type.
3.4 Repository
The studied material is deposited in the collection of theDivision of Historical Geology/Palaeontology, Universityof Bremen, Germany.
4. Results and discussion
Early Maastrichtian to Quaternary assemblages of calcareous dinoflagellate cysts of two ODP cores, Hole

15

747A, central Kerguelen Plateau and Hole 761B, Wombat
Plateau (Figure 1), were studied at a relatively low sample density to obtain a general overview of the evolutionof this group during the Cenozoic and to map differencesin stratigraphic and latitudinal distribution patterns, aswell as to link observed shifts in associations and abundance to major climatic changes. As both studied cores
are characterised by different hiatuses though, a directcomparison is possible for some stratigraphic intervals
only (see Figure 6).
4.1 Abundance of calcareous dinoflagellate cysts
Results The absolute abundance of calcareous dinoflagellate cysts in Hole 747A shows remarkable variability,from <100 to a maximum of >50 000 cysts per gram sediment (Figure 2). Major changes in cyst frequency occur
between the Early Maastrichtian and Early Paleocene, as
well as between the Early Eocene and Early Oligocene.
Both intervals of change were accompanied by drasticchanges in the sedimentation rate, though, which might
have contributed to the changes in absolute cyst abundance (see Section 2). Calcareous cysts were again common in the Middle Miocene, but abundance gradually
decreased towards the core-top, with a minimum in thelatest Pliocene and Pleistocene.
The relative abundance of calcareous dinoflagellate
cysts in Hole 761B generally varies from rare to few,
interrupted by three major peaks where calcareous cysts
are common to abundant. Comparable to Hole 747A, amajor abundance peak occurred in the Early Paleocene.
However, in contrast to Hole 747A, the abundance peakin Hole 761B does not correlate with a significant
decrease in the sedimentation rate. The abundance
increase in both cores is mainly due to the numerous
appearance of a single species, Cervisiella operculata.
However, differently from Hole 761B, the high abundance of C. operculata in the Paleocene of Hole 747A wasaccompanied by an additional taxon, Fuettererella flora, aspecies which is only of minor quantitative importance in
the Paleocene of Hole 761B.
The second abundance peak in Hole 761B occurred in
the Middle Eocene, and the third in the Pleistocene, withthe latter being attributed to the high abundance ofCalciodinellum albatrosianum. In contrast to the generalabundance decrease since the Early Miocene, and theminimum in the Pleistocene, in Hole 747A, a generalabundance increase was observed in Hole 761B since theMiddle Miocene, with a maximum in the Pleistocene.
Discussion The significant abundance increase of calcareous cysts following the K/T boundary coincides witha drastic abundance decrease and the mass extinction of
taxa of other calcareous phytoplankton (e.g. Henriksson,
1996). This increase of calcareous dinoflagellate cysts,
which has been reported as a ‘Thoracosphaera’ bloom(Thierstein, 1981; Eshet et al., 1992), has been recorded16

Streng, Hildebrand-Habel, Willems

in many oceanic sections world-wide (e.g. Thierstein,
1981; Perch-Nielsen et al., 1982; Fütterer, 1990;
Hildebrand-Habel et al., 1999; Hildebrand-Habel &Willems, 2000). It obviously varied in intensity with latitude, at least in the oceanic environment, being more pronounced at lower latitudes than at higher latitudes (e.g.
Hildebrand-Habel&
Streng,2003).
This‘Thoracosphaera’ bloom generally means the acme ofCervisiella operculata (formerly Thoracosphaera operculata), a species that obviously reacted opportunistically tothe rapid environmental changes at the K/T transition (seealso Section 4.2).
The slight abundance increase in the middle Miocene
sample 9H-5 (120-121cm) of Hole 747A falls in the range
of a short-lived decrease in δ18O values (Wright & Miller,
1992), indicating the mid-Miocene climatic optimum.
The steady decrease in abundance following this event
correlates with an increase of d18O values because of the
progressive temperature drop and the growth of the
Antarctic Ice-sheet (Zachos et al., 2001). This Late

Miocene cooling caused an increase in biosiliceous sedimentation (Shipboard Scientific Party, 1989) and a distinct deterioration of the living conditions for calcareous
dinoflagellates in high latitudes at Site 747, as reflected in
the steady abundance decrease. Obviously, the low-latitude assemblages of Hole 761B were also affected by thiscooling, but in contrast to the high latitudes, the low-latitude assemblages experienced an increase in abundance
during the Late Neogene, implying an improvement of theliving conditions for calcareous dinoflagellates in low latitudes, although diversity decreased.
4.2 Diversity
Results In total, 35 morphotypes of calcareous dinoflagellate cysts (excluding Thoracosphaera heimii) havebeen distinguished in the studied samples of Hole 747A.
The species richness of the individual samples varies significantly throughout the section, ranging from monospecific associations to assemblages with a maximum of 11morphotypes (Figure 2). With four taxa, the diversity was

Figure 2: Abundance of calcareous dinoflagellate cysts (B and D) and species richness (A and C) in ODP Holes 747A (left) and 761B (right). B)
Absolute abundance of cysts (cysts/g sediment). D) Relative abundance of cysts (rare to abundant). Note logarithmic (upper scale, dotted line) andnormal scales (lower scale, dashed line) in B

Long-term evolution of calcareous dinoflagellate associations

relatively low in the Early Maastrichtian, but increased
dramatically to 11 in the Paleocene. Early Oligocene
diversity was again relatively low (five morphotypes) andincreased anew in the Late Oligocene and Early Miocene(up to 10 morphotypes). A steady decrease in diversity
was observed in the younger samples, culminating inmonospecific associations in the latest Pliocene andPleistocene.
In Hole 761B, the total number of calcareous dinoflagellate taxa (47) is much higher than in Hole 747A.
Additionally, the species richness of the individual samples generally exceeds those of Hole 747A. However, asin Hole 761B, diversity was very low in the samples preceding the K/T boundary (four to five morphotypes),
although an increase had begun in the sample closest to
the boundary. With 11 taxa, diversity reached a maximum
in the Early Danian. Diversity remained relatively highthroughout the remaining Cenozoic (eight to 11 taxa),
except for the Pleistocene, which had a relatively low
species richness of six taxa.
Discussion The general diversity increase above theK/T boundary may be attributed to the same reasons as
the abundance increase discussed above. The drastic
abundance decrease, or even extinction, of most calcareous nannofossil taxa at the K/T boundary (e.g.
Henriksson, 1996), made a rapid increase in abundanceand diversity of calcareous dinoflagellate cysts possible,
most likely due to the extinction of competitors and/or
predators, and through the availability of nutrients.
Generally speaking, some calcareous dinoflagellate
species, in particular Cervisiella operculata andFuettererella flora, reacted opportunistically, like typicaldisaster or r-selected taxa, by exploiting the nutrients andreproducing rapidly in the aftermath of the K/T event.
The low species richness in the Early Oligocene ofHole 747A may correspond to the Early Oligocene glaciation. Low diversity during this time has also been reported for high-latitude planktonic foraminifera associations(Jenkins, 1993). The diversity of calcareous cysts slightly
increased after this glaciation event.
The observed drastic decrease in species richness
since the Pliocene at both sites can be explained by the
progressive water-mass cooling of the Southern
Hemisphere (e.g. Kennett, 1982) linked with the onset of
the Northern Hemisphere glaciation. However, in contrast
to the low latitudes, where species richness of calcareous
dinoflagellate cysts halved since the Late Pliocene,changes at high latitudes were more severe and produced
monospecific associations, with Caracomia arctica being
the sole calcareous dinoflagellate species capable ofnegotiating the physical barrier of carbonate secretion incold environments (Streng et al., 2002; Hildebrand-Habel& Streng, 2003).
4.3 Shifts in associations of calcareous
dinoflagellates

17

Discussion Major shifts in the associations of calcareous dinoflagellates since the Late Cretaceous have generally been attributed to major changes in the palaeoenvironment, induced by severe climatic or oceanographic
changes (Hildebrand-Habel et al., 1999; HildebrandHabel & Willems, 2000). Because of the low sample density in this study, fluctuations in the associations of calcareous dinoflagellates are not surprising. Consequently,
uncertainties exist regarding the significance of theobserved shifts. However, since calcareous dinoflagellate
taxa are generally long-ranging (e.g. Hildebrand-Habel &Willems, 2000), and shifts in associations are obviously
linked to long-term environmental changes, the influenceof environmental changes on the associations cannot bedismissed.
4.3.1 The Cretaceous/Tertiary transition
Results In both holes, the K/T transition is characterised by a pronounced change in calcareous dinoflagellate assemblages (Figures 3, 4). Maastrichtian assemblages were characterised by low diversity and the dominance of Pirumella krasheninnikovii, a species which istypical in oceanic sediments of this age. Early Paleocene
assemblages, on the contrary, were highly diverse anddominated by Cervisiella operculata. However, no mass
extinction event of calcareous dinoflagellate taxa wasobserved to occur at the K/T boundary: although sometaxa disappear at or prior to the boundary, many taxa persist into the Paleocene, where typical Late Cretaceous
taxa, for instance P. krasheninnikovii and
Orthopithonella? congruens, then drastically decrease inabundance.
Discussion Both sites show the same changes in associations and abundance of calcareous dinoflagellate cyststhat have already been reported elsewhere from the K/Ttransition (Kienel, 1994; Hildebrand-Habel et al., 1999;
Hildebrand-Habel & Streng, 2003). These remarkablechanges are mainly due to the nearly global‘Thoracosphaera’ bloom discussed above. However, incontrast to all other oceanic assemblages studied so far,the Early Paleocene assemblage in Hole 747A is not dominated by C. operculata, but by Fuettererella flora (52%of the association). C. operculata accounts for only 21%
and atypically achieves its highest abundance in the Late
Paleocene. Similar results have been reported byHildebrand-Habel & Streng (2003) from Maud Rise
(Weddell Sea, South Atlantic Ocean), where F. flora andC. operculata also dominated the Early and Late
Paleocene. Both taxa seem to represent essential elementsof a typical high-latitude association of calcareous
dinoflagellate cysts in the Paleocene, as already suggested by Hildebrand-Habel & Streng (2003). The existenceof characteristic Early Paleocene high-latitude nannofossil assemblages suggests transition from a low thermal
gradient in the Late Cretaceous to a more significant thermal gradient in the Danian, as already noted by Wei &18Streng, Hildebrand-Habel, Willems

Pospichal (1991).
4.3.2 The Paleocene-Eocene transition at
Site 747
Discussion The Late Paleocene-Early Eocene interval
was a time of major change in oceanic circulation andglobal climate, as reflected by evolutionary radiation andincreased diversity of marine biota (e.g. Berggren et al.,1998), however, no corresponding changes in calcareous
dinoflagellate associations are obvious in Hole 747A.
Although Cervisiella operculata abruptly disappeared at
the end of the Paleocene, and Fuettererella belliata
appeared with already relatively high abundance in the
Early Eocene, these changes do not seem to be directly
linked with the severe climatic warming at this time,
although a more detailed study might be more revealing.

Figure 3: Stratigraphy, general lithology and percentage occurrence of calcareous dinoflagellate taxa in ODP Hole 747A. Calcareous dinoflagellates
have been grouped according to their archeopyle type as follows: A) taxa with a small, apical archeopyle involving the single plate 3’ (Type A); B)
taxa with a mesoepicystal archeopyle involving three apical and all intercalary plates (Type (3AtI)); C) taxa with an epitractal archeopyle involving
all apical, intercalary and precingular plates; D) taxa with an unknown archeopyle type; E) pithonelloid species with small circular apertures; F)shells of the coccoid stage of Thoracosphaera heimii

Long-term evolution of calcareous dinoflagellate associations

19

Figure 4: Stratigraphy, general lithology and percentage occurrence of calcareous dinoflagellate taxa in ODP Hole 761B. Calcareous dinoflagellates
have been grouped according to their archeopyle type as in Figure 3

4.3.3 Early Oligocene of Site 747
Results The Early Oligocene assemblage of Site 747 isremarkable. It is distinguished by low diversity and domination by a single species, Pernambugia? patata, whichforms 93% of the association (Figure 3). This taxon ischaracterised by an irregular shape and a unique type of
epitractal archeopyle. It has only been found at Site 747
as yet (Streng et al., in press).
Discussion The Eocene-Oligocene transition is char-acterised by a lowering of atmospheric temperatures,
ocean cooling associated with stronger thermal stratification, and the initiation of the Antarctic Circumpolar
Current and Antarctic glaciation (Jenkins, 1993; Berggren
et al., 1998). Drastic cooling of Early Oligocene surfacewaters in the southern Indian Ocean is indicated by a sudden increase in the percentage of cooler water calcareous
nannoplankton taxa, an increase in planktonic
foraminifera d18O values, and the increase of biosiliceous
sediments on the Kerguelen Plateau (Wise et al., 1992;

20

Streng, Hildebrand-Habel, Willems

Zachos et al., 1992). Moreover, typical Antarctic assemblages developed within the radiolarians (Lazarus &Caulet, 1993). Hence, it is assumed that P.? patata might
be a typical representative of an Antarctic calcareous
dinoflagellate cyst assemblage in the southern Indian
Ocean and, analogous to the radiolarians, indicative of
rapidly-cooling surface-waters in the Early Oligocene.
4.3.4 Middle to Late Miocene transition at
Site 747
Results The Early and Middle Miocene were clearly
dominated by a single species, Pirumella edgarii, which
achieved, for example, more than 90% of the associationin the late Middle Miocene. The association changed
abruptly in the Late Miocene: P. edgarii disappeared completely, and the cold-water species Caracomia arctica(Streng et al., 2002), became abundant together withanother potential cold-water taxon, Calciodinellum kerguelense (Figure 3).
Discussion The Miocene of the southern Indian
Ocean was characterised by a warming trend in the Early
to early mid-Miocene, associated with a reduction of the
Antarctic ice-cover (Zachos et al., 2001). Subsequently, a
cooling trend was initiated in the Middle Miocene andcontinued into the Late Miocene (Jenkins, 1993). This
cooling was accompanied by the reestablishment of amajor ice-sheet on Antarctica (Zachos et al., 2001). The
expansion of the East Antarctic Ice-sheet in the latest
Middle Miocene is correlated with a decline of surfacewater temperatures in the Southern Ocean, followed by aprogressive glaciation of West Antarctica. Cold Antarctic
surface-waters expanded northwards and initiatedincreased upwelling and biogenic productivity in the Late
Miocene (Kennett, 1977; Jenkins, 1993). Although calcareous dinoflagellate cysts did not contribute to thisincrease in biogenic productivity, they nonethelessreflected the climatic changes of the period described.
The dominance of P. edgarii reflects relatively warm temperatures prior to the intensification of the Antarctic
glaciation. The increased abundance of C. arctica and theappearance of C. kerguelense in the Late Miocene is interpreted as reflecting the major cooling of the Southern
Ocean during this time. This distinct shift in the associations matches the results of Hildebrand-Habel & Streng(2003) from the eastern Weddell Sea, Site 689. Similarly
to Hole 747A, the Early and Middle Miocene of Hole
689B was dominated by P. edgarii, which was followed
by a dominance of C. arctica in the latest Middle
Miocene, after the mid-Miocene climatic optimum. The
coincident results from different regions suggest that thedescribed change in associations, from a dominance of P.
edgarii to a dominance of C. arctica, is characteristic for
the Miocene of high latitudes and marks the distinct climatic change at the mid-Miocene climatic optimum.
The abrupt, common occurrence of C. kerguelense
and C. arctica at the same time during the Late Miocene

indicates that C. kerguelense might be, just like C. arctica, adapted to cool, temperate regions. In contrast to C.
arctica, however, C. kerguelense obviously did not succeed in adapting to the increased cooling at the beginningof the Late Pliocene.
4.3.5 Pliocene to Pleistocene at Site 747
Results The Pliocene-Pleistocene evolution of calcareous dinoflagellate cyst associations of Hole 747A is characterised by two major changes. The species composition
drastically changed from the Late Miocene to Early
Pliocene and from the Early to Late Pliocene. Early
Pliocene assemblages are typified by a quantitatively-balanced occurrence of four main taxa (Pirumella edgarii,
Caracomia arctica, Calciodinellum kerguelense andFuettererella flora). They thus differ from the Late
Miocene assemblages, which were dominated by C. arctica and C. kerguelense, and those from the early Late
Pliocene to Pleistocene, which were dominated by C. arctica. It is worth noting that two species disappeared at theend of the Early Pliocene: 1) C. kerguelense, a species
that had appeared in the Late Miocene and probably wasadapted to cooler environments to a certain degree; and 2)
P. edgarii, a species that dominated throughout the Earlyand Middle Miocene. P. edgarii had been absent in the
Late Miocene, but had reappeared in high abundance inthe Early Pliocene before it finally disappeared in the Late
Pliocene.
Discussion The described major shifts in calcareous
dinoflagellate cyst associations from the Early to Late
Pliocene occurred simultaneously with a rapid increase inδ18O values, reflecting the onset of the Northern
Hemisphere glaciation and an intensified general cooling
trend (e.g. Zachos et al., 2001), accompanied by a global
lowering of sea-level. A slight warming in the Early
Pliocene, however, preceded the Pliocene cooling (e.g.
Thiede & Vorren, 1994; Jenkins, 1993). It caused a temporary increase in surface-water temperatures of 4˚C in
the southern Indian Ocean (Bohaty & Harwood, 1998).
The balanced Early Pliocene assemblages, and the reappearance of P. edgarii, correlate with this warming trend,
whereas the rapid Late Pliocene cooling is reflected in thediversity decrease and dominance of the cold-water
species C. arctica (see also Hildebrand-Habel & Streng,2003).
4.3.6 Neogene and Quaternary of Site
761
Quaternary mid- and low-latitude pelagic assemblages ofAtlantic calcareous dinoflagellate cysts are typically dominated by few species. Calciodinellum albatrosianum,
Calciodinellum levantinum (= Sphaerodinella tuberosa ofmany authors: see Meier et al., 2002), and Leonella granifera are the most common taxa (e.g. Höll et al., 1999;
Esper et al., 2000; Vink et al., 2000). Calciodinellum
operosum, Pernambugia tuberosa, Scrippsiella spp. and aLong-term evolution of calcareous dinoflagellate associations

few additional taxa occur only subsidiarily, infrequently,
or are regionally restricted. The Pleistocene assemblageof Hole 761B, dominated by C. albatrosianum, is no
exception. These ‘modern’ assemblages differ distinctlyfrom known pre-Quaternary (= ‘fossil’) assemblages, andit has been puzzling when the change from ‘fossil’ to‘modern’ assemblages took place. The Neogene assemblages of Hole 761B provide a first clue to this problem.
Results The Early Miocene is dominated by typical‘fossil’ taxa, with Cervisiella saxea being the most common species. Modern species (Scrippsiella regalis and P.
tuberosa) constitute only about 5% of the association. In
the Middle Miocene, the proportion of modern taxa
increases to 37%, mainly due to the occurrence of C.
albatrosianum in relatively high numbers (26% of theassociation) and the decline of C. saxea. The Late
Pliocene assemblage can already be compared with themodern associations, since it is essentially composed ofmodern taxa (82%) and characterised by a dominance of
C. albatrosianum. Another puzzling change becomes
obvious when comparing the cyst size of specimens of C.
albatrosianum from the Middle Miocene as part of a ‘fossil’ assemblage with those from the Late Pliocene andPleistocene, representing ‘modern’ assemblages. With
diameters of 31.6 to 47.5µm (mean = 38.6µm), Middle
Miocene cysts of C. albatrosianum are distinctly larger
than those from the Late Pliocene and Pleistocene, whichhave diameters of 24.2 to 36.3µm (mean = 28.4 and28.2µm), respectively (Figure 5). Additionally, the rangeof the cyst diameters gradually narrowed from 15.9µm in
the Middle Miocene to 8.5µm in the Pleistocene.
Discussion After the mid-Miocene climatic optimum,
the climatic evolution of the Southern Hemisphere wasmainly influenced by the development of the Antarctic
Ice-sheet. Linked with expansions of the Antarctic Icesheet were northward penetrations of the cold Antarctic
water-masses, also connected to Middle and Late
Miocene cooling in the eastern Indian Ocean, as indicated by the arrival of cool-water foraminifera (e.g.
Zachariasse, 1992). During the latest Miocene and earliest Pliocene, glaciation of Antarctica progressed, ocean
circulation intensified, the temperature gradient between
polar and equatorial regions increased and sea-level experienced a major lowering. Generally warm conditions forthe remaining Early Pliocene (e.g. Thiede & Vorren,1994), accompanied by a reduction of the Antarctic Iceshield (e.g. Crowley & North, 1991), were broken off by
the Late Pliocene cooling and the onset of Northern
Hemisphere glaciation. Therefore, two potential reasons
might have been the trigger for the development of thetypical, modern low-diversity calcareous dinoflagellate
cyst assemblages: 1) the Late Miocene cooling; and/or 2)
the continuation of this trend with the beginning of theLate Pliocene. Further studies are needed to clarify if one
or both cooling events are responsible for the shift to21

modern assemblages and to verify a possibly gradualdevelopment from ‘fossil’ to ‘modern’ assemblages.
Additionally, the significance of variations of the cyst
diameter, especially of C. albatrosianum, as an indicatorof environmental change must be proven in further studies from different localities.

Figure 5: Frequency distribution of cyst diameters of Calciodinellum
albatrosianum in three succeeding samples of the Neogene of Hole
761B (Wombat Plateau) illustrating the general decrease of the diameterand its range (shaded area) from the middle Miocene to the Pleistocene(n = number of measured specimens)

4.4 Variations in the relative abundanceof calcareous dinoflagellate archeopyletypes
During the past few decades, calcareous dinoflagellate
cysts have mainly been classified according to the crystallographic orientation of the wall-forming crystals (e.g.
Keupp & Mutterlose, 1984; Keupp, 1987; Kohring,1993). Great efforts have been made by Hildebrand-Habel
et al. (1999), Hildebrand-Habel & Willems (2000) and
Hildebrand-Habel & Streng (2003) to correlate relative
abundance of these wall-types with times of major
palaeoenvironmental changes. To determine the exact orientation of the c-axes of the wall-forming crystallites, andthus the wall-type, the cysts have to be examined in 1.5 to
3µm thin-sections under polarised light using a method
introduced by Janofske (1996). This method has been
applied to many species recently, but numerous species,
especially from the Cretaceous, have still not been examined. The wall-type of these species has generally beeninterpreted from SEM examinations (morphologicalcross-section of the wall) and comparison with species

22

Streng, Hildebrand-Habel, Willems

with a verified wall-type. This lack of reliable information
on wall-types arises from the method of Janofske (1996),
which is not practicable for all cysts. Especially from double-layered cysts, with one thick and one thin layer, noreliable information is obtainable, as the interferencecolours of the thick wall superimpose those of the thinner
layer. Because of the missing information on the walltypes of many species, interpretations concerning fluctuations of wall-types must be regarded as tentative.
Furthermore, the only distinct and pronounced fluctuationof wall-types recognised until now occurs at the K/T transition: the oblique and radial wall-types, which prevailed
in the latest Cretaceous, gave way to the tangential walltype in the Early Paleocene. The duration of the prevalence of the tangential wall-type, however, obviously
depends on the individual locality (compare HildebrandHabel et al., 1999; Hildebrand-Habel & Willems, 2000;
Hildebrand-Habel & Streng, 2003).
For the reasons outlined above, fluctuations of the relative abundance of wall-types have not been analysed in
the studied cores of Sites 747 and 761. Instead, we
focussed on fluctuations in the tabulation reflected by thearcheopyle in order to unveil and verify a possible ecological control of these fluctuations.
Results Species with a large archeopyle, i.e. species
whose archeopyle involves more than one plate (seeSection 3), appear, though in low numbers, in the Early
Paleocene of Hole 747A and show a first peak in the relative abundance of cysts in the Oligocene due to the mass
appearance of Pernambugia? patata. However, their firstsignificant contribution to the assemblages in relative
terms, as well as in number of species, is in the Late
Oligocene, where the number of species with a large
archeopyle for the first time exceeds the number of
species with a small archeopyle. Thenceforward, species
with a large archeopyle are prominent members of theassociations, though in varying number and relative abundance. Correspondingly, the relative abundance ofarcheopyle types in Hole 747A shows notable fluctuations
throughout the studied section. Small archeopyles(archeopyles that involve a single plate; see Section 3)
dominate the Maastrichtian to Early Eocene and the Early
to Middle Miocene. Accordingly, large archeopyles peakin the Early Oligocene, earliest and Late Miocene, and in
the Late Pliocene to Pleistocene. A balanced ratio of botharcheopyle categories is present in the Early Pliocene (seeFigure 6).
Analogous to Hole 747A, species with a large
archeopyle appear in the Early Paleocene of Hole 761B
and become significant members of the associations (withrespect to the number of species) in the Early Miocene.
With a dominance of small archeopyles in the
Maastrichtian to Early Paleocene, the relative abundanceof archeopyle types of Hole 761B shows a similar pattern
as in Hole 747A. The relative abundance pattern of Hole
761B also corresponds to Hole 747A in the Late Pliocene

to Pleistocene samples, with a dominance of large
archeopyles (Figure 6). Furthermore, small archeopyles
are relatively abundant in the Middle Eocene and Early
Miocene. However, Late Paleocene to Middle Eocene
samples have relatively high numbers of species with an
unknown archeopyle type, amongst them being the abundant problematic taxa Thoracosphaera? prolata andOrthopithonella? minuta (see Taxonomic notes, below).
The presence of those species unfortunately biases thefluctuation pattern of the archeopyle types and makes aninterpretation impossible.
Discussion Fluctuations in the abundance of the prevailing archeopyle type in Hole 747A correlates with general trends in Cenozoic climatic evolution, with species
with small archeopyles being characteristic of warmer
periods and species with large archeopyles of cooler intervals. Thus, the high relative abundance of species withsmall archeopyles during the Paleocene and Early Eocene
corresponds to the Palaeogene interval of global warming,
culminating in the Early Eocene climatic optimum(Zachos et al., 2001); the higher abundance of small
archeopyles in the Early to Middle Miocene reaches amaximum just after the mid-Miocene climatic optimum;
and the Early Pliocene excursion correlates with the subtle warming trend at this time (Ciesielski & Grinstead,
1986; Bohaty & Harwood, 1998; Zachos et al., 2001).
High values in the relative abundance of large archeopyles, on the contrary, correlate with major cooling events
triggered by the increasing Antarctic glaciation. As such,abundance peaks in the Early Oligocene and earliest
Miocene follow the first major glaciation episodes (Oi-1and Mi-1; Zachos et al., 2001). Comparably, the Late
Miocene and Late Pliocene to Pleistocene maxima correspond to the re-establishment of a major ice-sheet on
Antarctica after the mid-Miocene climatic optimum, andthe continuation and intensification of the general
Cenozoic cooling with the onset of the Northern
Hemisphere glaciation, respectively.
Only in the Early Paleocene and the Late Pliocene toPleistocene do fluctuations in the relative abundance ofarcheopyle types in Hole 761B correspond to those inHole 747A. In contrast to Hole 747A, Late Paleocene to
Middle Miocene fluctuations cannot be correlated withclimatic variations. This may partly be due to the highabundance of species with an unknown archeopyle type in
Hole 761B, biasing the fluctuations. However, in times of
low abundance of these problematic species, for instancein the Early and Middle Miocene, the ratio of small tolarge archeopyles depicts trends different from Hole
747A. This implies that the correlation of the archeopyle
ratio with the climatic development observed in Hole
747A is either of only local reliability, or distinctive only
for high latitudes. The latter possibility is supported by
the data of Hildebrand-Habel & Streng (2003) from Hole
689B, Maud Rise, Weddell Sea. Their results show similar trends, although less clearly than in Hole Site 747A.

Long-term evolution of calcareous dinoflagellate associations

23

Figure 6: Correlation and comparison of the two studied ODP cores based on relative abundance of calcareous dinoflagellate archeopyle types. Three
categories are distinguished: small archeopyle type = archeopyles including a single apical plate; large archeopyle type = archeopyles involving morethan one plate; unknown archeopyle type = archeopyle type of individual taxa can not be designated because of unknown number of involved plates
or the absence of an archeopyle. Arrows with nannofossil zones indicate sample positions. Nannoplankton zonation according to Martini (1971) andSissingh (1977) as provided by Schlich et al. (1989) and Haq et al. (1990)

5. Conclusions
The comparison of two cores from the eastern and southern Indian Ocean evinced that the long-term Cenozoic
evolution and composition of calcareous dinoflagellate
cyst assemblages seem to be effectively influenced andcontrolled by the major climatic changes of this time-period. The different latitudinal positions of the cores made it
possible to investigate the varying developments of typical high- and low-latitude associations since the beginning of the Early Paleocene. Despite the different species

composition, high- and low-latitude associations generally react coevally to climatic and environmental changes,
though often in an opposite way, or with different intensity. The following intervals of major shifts in calcareous
dinoflagellate associations, and their relationship tosevere climatic or environmental changes, became obvious:
1) K/T transition: Calcareous dinoflagellate cyst associations of both sites responded to the severe environmental deterioration following the K/T boundary event with a24Streng, Hildebrand-Habel, Willems

striking increase in abundance and diversity, as well as amajor change in the species composition. The opportunistic species Cervisiella operculata typically characterises
the Early Paleocene assemblages but, in contrast to low
latitudes where it exclusively dominates the associations,high-latitude assemblages are additionally influenced by
the high abundance of Fuettererella flora. These two
species probably represent typical components of a highlatitude association in the Early Paleocene. No mass
extinction event of calcareous dinoflagellate cysts wasrecognised at the K/T boundary.
2) Early Oligocene: The Early Oligocene assemblage ofthe high-latitude site is dominated by Pernambugia?
patata, a species probably indicating the Early Oligocene
temperature drop and the onset of continental ice-accumulation on Antarctica.
3) Neogene: The development of the associations during
the Neogene is quite opposite at the two sites. The highlatitude site clearly illustrates the overall progressive
cooling trend by a general decrease in abundance anddiversity. Additionally, the species composition of theindividual intervals revealed ‘warmer’ and ‘cooler’ associations. Higher abundance of Pirumella edgarii is probably indicative of warmer periods, i.e. the Early andMiddle Miocene and the Early Pliocene, whereas
Caracomia arctica and Calciodinellum kerguelense arecharacteristic of cooler periods, like the Late Miocene andLate Pliocene to Pleistocene. The low-latitude site, on thecontrary, experienced a general increase in the abundanceof cysts during the Neogene and a concomitant reductionof diversity towards typical modern associations. Thechange to a modern association occurred in the late
Middle Miocene to early Late Pliocene.
Besides the observed fluctuations in the associations,shifts in the stratigraphic distribution pattern of the ratioof small to large archeopyles also revealed a distinct correlation with Cenozoic climatic development, particularly
at high latitudes. Taxa with small archeopyles seem toprevail during warmer periods, like the Late Cretaceousand the Paleocene, whereas taxa with large archeopyles
are representative of cooler periods, like the Late Miocene
and Late Pliocene.
Despite the identification of the distinct correlations
described above, more detailed and higher resolution
studies of selected stratigraphic intervals are needed toconfirm the observed connections between the association
dynamics of calcareous dinoflagellate cysts and the climatic evolution of the Cenozoic.
6. Taxonomic notes
Most species found in the analysed samples of ODP Holes
747A and 761B are well-known. However, some taxa
need further explanation, because their assignment to a
distinct genus is only tentative, or impossible. Many ofthese taxa may represent new species, but the lack of a
sufficient number of specimens on one hand, and uncertainties concerning the crystallographic ultrastructure on

the other, allow only an informal description, or a description using open nomenclature. Species are sorted according to the different archeopyle categories summarised inStreng et al. (in press).
6.1 Species with an apical archeopyleincluding the single plate 3’
Cervisiella sp. aff. Operculodinella reticulata Kienel,
1994
Plate 1, Figure 9
Remarks: The three specimens of Cervisiella sp. aff.
Operculodinella reticulata form a transition between
Cervisiella operculata (Bramlette & Martini, 1964)
Streng et al., in press and Operculodinella reticulata
Kienel, 1994. The outer cyst-surface is characterised byan irregular pattern of numerous pseudopores which aresurrounded by strong ridges. This pattern is generally
similar to that of C. operculata, however, C. sp. aff. O.
reticulata bears fewer pseudopores and a more solid
development of ridges. Size and number of pseudopores
and ridges, in turn, resemble those of O. reticulata, but
pseudopores of O. reticulata are arranged in regular rows,
which run parallel to the equatorial plane and ascend in
the sulcal area, reflecting possibly a reduced tabulation.
Cysts of C. sp. aff. O. reticulata are spherical in shape(39.6, 39.8 and 47.4µm in diameter) and bear a circular toslightly angular, apically-situated archeopyle measuring
35 to 42% of the cyst diameter. As the archeopyle is comparable to that of C. operculata, the three specimens havebeen assigned to the genus Cervisiella and probably represent an extremely rough-textured variation of C. operculata.
Range: Upper Paleocene (within interval NP11-NP13) ofHole 747A, Kerguelen Plateau.
Cervisiella? sp. aff. Cervisiella saxea (Stradner, 1961)
Hildebrand-Habel et al., 1999
Plate 1, Figure 11
Remarks: The single specimen of Cervisiella? sp. aff. C.
saxea is spherical in shape with a diameter of 34.9µm andhas a 3.1µm-thick single-layered wall. The circulararcheopyle measures 10.5µm in diameter and represents
the single plate 3’. The cyst resembles C. saxea concerning size, archeopyle type and the general habit of the crystallites, however crystallites of Cervisiella? sp. aff. C.
saxea are more prominent and show a coarser, probably
diagenetically altered, habit.
Range: Middle Miocene (NN6) of Hole 761B, Wombat
Plateau.
Fuettererella? sp. aff. Calciodinellum sp.1
Plate 1, Figure 5

Long-term evolution of calcareous dinoflagellate associations

Remarks: This specimen is spherical, 29.0µm in diameter, and strikingly resembles Calciodinellum sp.1 (Plate 3,
Figures 6-9), but bears a circular, 9µm wide archeopyle.
The archeopyle outline and the probably tangential ultrastructure (see Remarks for Calciodinellum sp.1), suggest
the accommodation of this specimen in the genus
Fuettererella.
Range: Upper Pliocene (NN16) of Hole 761B, Wombat
Plateau.
Gen. et sp. indet. aff. Pirumella williambensonii (Bolli,1978) Williams et al., 1998
Plate 1, Figure 21; Plate 2, Figure 7
1988 Orthopithonella williambensonii (Bolli, 1978):Willems, p.449-451, pl.4, figs 17-19.
1997 Orthopithonella williambensonii (Bolli, 1978):
Hildebrand-Habel & Willems, p.185, pl.3, figs 7-8.
Remarks: Pirumella williambensonii (Bolli, 1978) is aproblematic taxon, as it probably accommodates several
different species. Bolli (1978) described P. williambensonii from Upper Jurassic strata as having a loose crystal
arrangement with large interspaces on the outer cyst-surface, a 10µm thick outer layer, and much thinner inner
layer of about 2µm. Keupp (1981) and Keupp & Ilg(1989) assigned specimens to P. williambensonii thatclosely resemble the type material of Bolli (1978), however no information on the number of wall-layers is given.
Keupp (1987) and Keupp & Kowalski (1992) assigned
single-layered specimens to P. williambensonii, whichshow a much coarser crystal arrangement than does thetype material. P. williambensonii sensu Kohring (1993) issingle-layered and exhibits no interspaces. In contrast,
Willems (1988) and Hildebrand-Habel & Willems (1997)
described clearly double-layered specimens as P.
williambensonii, whereas both layers are more or lessequal in thickness. However, none of the depicted specimens of the mentioned authors exactly corresponds to thedescription given by Bolli (1978), or the information
given is insufficient for an exact assignment. Therefore, P.
williambensonii can be subdivided into four morphotypes, which are separated morphologically as well as
stratigraphically: 1) P. williambensonii sensu stricto introduced by Bolli (1978) from the Upper Jurassic.
Tentatively assigned to this morphotype are the specimens described by Keupp (1981) and Keupp & Ilg (1989)
from the Lower Hauterivian and Callovian, respectively;
2) P. williambensonii sensu Keupp (1987) from the Albian
is single-layered and bears coarse crystallites; 3) P.
williambensonii sensu Willems (1988) (described as
Orthopithonella williambensonii Willems, 1988 n.
comb.), known from the Middle Coniacian to Upper
Santonian, is characterised by its double-layered wall anda potential radial ultrastructure; 4) P. williambensonii
sensu Kohring (1993), from the Middle Eocene, is single-

25

layered and shows no interspaces between the crystals.
The three specimens from the Wombat Plateau correspond to the description and depicted specimens of thethird morphotype, P. williambensonii sensu Willems(1988). The cysts are spherical or slightly ovoid and havemaximum diameters of 41, 54 and 63µm. The crystals of
the double-layered wall appear radially arranged in crosssection. Both layers are similar in thickness, although thedimensions of the outer layer slightly exceed those of theinner layer; resulting thickness of wall about 6.5µm. The
inner wall is built of massive, densely packed rhombohedrons; the outer wall, in contrast, is constructed of loosely arranged, bar-like crystals. The radial ultrastructure ofthis morphotype is suggested by Willems (1988) bymeans of SEM examinations of cross-sections of the wall.
Range: Campanian (within interval CC22-CC24) andUpper Maastrichtian (CC25) of Hole 761B, Wombat
Plateau.
Gen. et sp. indet. aff. Tetramerosphaera lacrimula
Willems, 1985
Plate 1, Figure 25; Plate 2, Figure 15
Remarks: Two specimens were found that superficiallyresemble Tetramerosphaera lacrimula Willems, 1985
concerning the drop-shaped appearance of the cyst andthe position of the archeopyle. However, they have a single-layered, relatively thick wall (4.7µm), in contrast to
the double-layered T. lacrimula, in which the individual
wall-layers are typically separated by ridges that reflect a
reduced tabulation. The wall of Gen. et sp. indet. aff. T.
lacrimula is built of radially-arranged, irregularly-shaped
rod-like crystallites. The habit of the crystallites mightsuggest a radial ultrastructure.
Range: Upper Maastrichtian (CC26) and Lower
Paleocene (NP3) of Hole 761B, Wombat Plateau.
Orthopithonella? sp. aff. Orthopithonella? globosa(Fütterer, 1984) Lentin & Williams, 1985
Plate 1, Figure 24; Plate 2, Figure 2
1990 Orthopithonella sp. cf. globosa (Fütterer, 1984):
Keupp, pl.15, figs 5-13.
1993 ?Orthopithonella globosa (Fütterer, 1984): Kohring,p.38-40, pl.29, figs a-f, pl.33, figs a-i.
1993 Orthopithonella sp. cf. globosa (Fütterer, 1984):
Monnet, p.24-25, pl.4, figs 10-13.
1994 ?Orthopithonella globosa (Fütterer, 1984): Keupp& Kohring, p.166, pl.2, figs 5-7.
?1997 Orthopithonella cf. globosa (Fütterer, 1984):
Hildebrand-Habel & Willems, p.185, pl.3, figs 5, 6.
2000 Orthopithonella globosa (Fütterer, 1984):
Hildebrand-Habel & Willems, fig.5h.
Remarks: Orthopithonella? globosa was first described26

Streng, Hildebrand-Habel, Willems

by Fütterer (1984) from the Upper Maastrichtian andLower Danian of the south-eastern Atlantic Ocean (ODP
Leg 74). Specimens from the type material are characterised by an exceptionally large size (84-132µm) and adouble-layered wall. The proximal layer is built of massive rhombohedrons and is about three times thicker thanthe distal layer. Crystallites of the thin distal layer are
arranged in a rosette-like pattern on the outer surface.
Similar cysts from Eocene to Miocene sediments havebeen assigned to O.? globosa by various authors (see synonymy), however, those specimens are significantly
smaller (reported range of diameter is 29 to 60µm) andlack the rosette-like pattern on the outer surface. We consider this morphotype to represent a congeneric, but different, species.
In addition to typical specimens of O.? globosa, several specimens were recognised in Holes 747A and 761B
that resemble the morphotype as described above. They
are spherical to slightly ovoid in shape and variable insize. The cyst diameter ranges from 35.1 to 67.0µm (mean= 53.6µm, n = 35). The wall is built of two layers which
are more-or-less equal in thickness. The inner layer ischaracterised by radially-arranged, columnar to shortcolumnar crystals. Crystals of the outer layer also appear
radial in cross-section, but the distal surface of the outerlayer may suggest an oblique ultrastructure, because its
pattern of interwoven crystallites is similar to the obliquedistal layer of Pirumella edgarii (Bolli, 1974) Lentin &Williams, 1993.
Specimens of O.? globosa from Holes 747A and 761B
differ from the described morphotypes in having large
diameters of 109-120µm and a massive inner layer.
Furthermore, they occasionally show the rosette-like pattern on the outer surface, whose presence obviously
depends on the state of preservation of the individual
specimens.

and hourglass-shaped, wall-forming crystals in cross-section. Cyst diameter ranges from 33.1 to 49.0µm (mean =41.7µm, n = 21). Morphotype 2 (Plate 1, Figures 10, 12)
was detected in Paleocene strata of Hole 747A and Hole
761B. Morphotype 2 is slightly smaller than Morphotype
1 (29.7 to 41.6µm in diameter; mean = 36.7µm, n = 15)
and the wall-forming crystals are of columnar shape incross-section, resembling the inner layer ofOrthopithonella? aequilamellata Willems, 1988 (Plate 2,
Figure 1). Morphotype 3 (Plate 1, Figure 13), from the
Paleocene of Hole 747A, differs from Morphotype 2 inadditionally possessing coarser crystallites. All morphotypes occasionally display a circular archeopyle.
Specimens resembling Morphotypes 1 and 2 havebeen accommodated within O. gustafsonii or described as
O. cf. gustafsonii and O. aff. gustafsonii, respectively, by
several authors (e.g. Fütterer, 1990; Keupp, 1992; Keupp& Mutterlose, 1994). Cysts comparable to Morphotype 3
were first described by Kienel (1994) from the Danian ofGermany and Denmark as Orthopithonella cf. gustafsonii
forma salebra. However, Streng et al. (2002) clearly distinguished those specimens from O. gustafsonii by meansof the archeopyle characteristics. Fütterer (1990) depicted
two specimens from the Maud Rise that closely resemble
Morphotypes 1 and 2, respectively, revealing the samedifferences concerning the habit of the wall-forming crystals. Additionally, just like Morphotypes 1 and 2, the specimens of Fütterer (1990) are from the Upper
Maastrichtian and the Danian.

Range: Lower Paleocene (NP2), Oligocene (NP24 orNP25), Lower Miocene (within interval NN1-NN4) and
Pliocene (nannoplankton zone unknown) of Hole 747A,
Kerguelen Plateau. Upper Maastrichtian (CC26) of Hole
761B, Wombat Plateau.

Remarks: Four specimens of Orthopithonella? sp. were
found which are all ovoid in shape, single-layered, andbear a subapically-situated circular to slightly angulararcheopyle. The specimens are 75.4 to 60.4µm long; thewidth of the cyst is about 85% of the length. The cyst wallis 5.5 to 6.0µm thick, built of numerous, radiallyarranged, slim crystallites. The outer surface of the cyst
appears smooth, because of the densely packed, tiny,equilateral-triradiate crystal tips. Orientation of the crystallographic c-axes of wall-forming crystallites is
unknown.

Orthopithonella? sp. aff. Orthopithonella gustafsonii(Bolli, 1974) Streng et al., 2002
Plate 1, Figures 10, 12, 13, 15
Remarks: Orthopithonella? sp. aff. O. gustafsonii ischaracterised by a spherical shape, a single-layered wall
built of radially-arranged crystallites, and a relatively uniform surface pattern of trigonal crystal tips. However,besides this general appearance, three different morphotypes were recognised, which are separated stratigraphically and show some morphological differences.
Morphotype 1 (Plate 1, Figure 15) was found in theLower Maastrichtian of Hole 747A and is characterisedby a less organised appearance of the outer cyst’s surface

Range: Lower Maastrichtian (CC24) and Lower
Paleocene (NP2) of Hole 747A, Kerguelen Plateau andUpper Paleocene (NP5) of Hole 761B, Wombat Plateau.
Orthopithonella? sp.
Plate 1, Figure 29; Plate 2, Figure 8

Range: Middle Eocene (NP14) of Hole 761B, Wombat
Plateau.
Pirumella sp. aff. Pirumella thayeri (Bolli, 1974) Lentin& Williams, 1993
Plate 1, Figure 17
1993 Obliquipithonella thayeri (Bolli, 1974): Versteegh,Long-term evolution of calcareous dinoflagellate associations

p.373, pl.7, figs 3-4.
Remarks: A single specimen of Pirumella sp. aff. P. thayeri was found, which is similar to a specimen described as‘Obliquipithonella’ thayeri by Versteegh (1993) from theUpper Pliocene. Both specimens resemble the type material of Bolli (1974), but since P. thayeri has as yet only
been reported from the Upper Jurassic and Lower
Cretaceous, a reappearance in the Pliocene is unlikely.
Therefore, no distinct allocation of these specimens has
been attempted, especially because P. thayeri is a poorlydefined morphotype and probably accommodates morethan one biological species.
Range: Lower Pliocene (nannoplankton zone unknown)of Hole 747A, Kerguelen Plateau.
Pirumella? sp. aff. Pirumella amplicrystallina(Pflaumann & Krasheninnikov, 1978) Lentin &Williams, 1985
Plate 1, Figure 28; Plate 2, Figure 12
Remarks: Cysts of Pirumella? sp. aff. P. amplicrystallina
measure 66 to 106µm in length (mean = 86.9µm, n = 29)
and 44 to 66µm in width (mean = 55.3µm, n = 29); specimens less than 75µm in length are scarce. Length andwidth are roughly positively correlated. The elongatedcysts are pear- or teardrop-shaped, with the antapical side
being blunt and the apical side pointed. Therefore, themaximum width is not in the medial position, but slightly
shifted antapically. The apically-situated archeopyle iscircular to slightly angular in outline, about 11 to 16µm in
diameter, and interpreted to represent the single apicalplate 3’. The single-layered wall is 5 to 6µm thick andappears to be built of obliquely oriented crystals arranged
in a loose pattern in surface view, however, in cross-section crystals appear in fact to be radially oriented, or possibly slightly oblique.
Specimens of Pirumella? sp. aff. P. amplicrystallina
are similar to several other Maastrichtian species in theirgeneral outer appearance, i.e. Pirumella krasheninnikovii(Bolli, 1974) Lentin & Williams, 1993, Pirumella usheri(Krasheninnikov & Basov, 1983) Lentin & Williams,
1993, and Pirumella amplicrystallina (Pflaumann &Krasheninnikov, 1978) Lentin & Williams, 1985.
However, in contrast to P. krasheninnikovii, cysts of P.?
sp. aff. P. amplicrystallina are single-layered and the outline is teardrop- or pear-shaped rather than elliptical.
Regarding the pear-shaped outline, they resemble
Pirumella usheri (Krasheninnikov & Basov, 1983) Lentin& Williams, 1993, which has, however, two layers. P.
amplicrystallina is single-layered, but its outline is elliptical not pear-shaped, and the shape appears more compact.
Range: Upper Maastrichtian (CC25 and CC26) of Hole
761B, Wombat Plateau.

27

6.2
Specieswithacombinationarcheopyle - mesoepicystal archeopyles
Calciodinellum sp. cf. Calciodinellum operosum
Deflandre, 1947
Plate 3, Figure 13
Remarks: A single specimen of Calciodinellum sp. cf. C.
operosum was found. It is distinguished from typical representatives of C. operosum Deflandre, 1947 by theabsence of the sutural ridge which separates the epicyst
from the cingulum. Apart from this, the tabulation patternis identical, as already noted in specimens from the Upper
Miocene of Algeria by Keupp et al. (1991). Furthermore,
the relatively large size (53.2µm) of this specimen isremarkable, which is distinctively larger than otherreported sizes of C. operosum.
Range: Lower Miocene (NN1) of Hole 761B, Wombat
Plateau.
Calciodinellum? sp.1
Plate 3, Figures 6-9
Remarks: Calciodinellum? sp.1 is generally very similar
to Calciodinellum levantinum Meier et al., 2002 regarding cyst size and general appearance. However, wallforming crystals of Calciodinellum? sp.1 are typicallysmaller than in C. levantinum and are additionally distally flattened in contrast to the pointed crystal tips of C. levantinum. Cysts of Calciodinellum? sp.1 are always spherical, measuring 25.5 to 32.3µm (mean = 28.8µm, n = 14)
in diameter; cyst wall is 1.6 to 2.2µm thick. The
archeopyle is mesoepicystal, angular in outline. Cysts arequestionably assigned to Calciodinellum since the orientation of the c-axes of wall-forming crystals has not been
examined. However, as the crystals resemble those of C.
levantinum, they most probably have a tangential orientation.
Range: Upper Pliocene (NN16) of Hole 761B, Wombat
Plateau.
Calciodinellum? sp.2
Plate 3, Figure 4
Remarks: Only two specimens of Calciodinellum? sp.2
were found. Both cysts are spherical, measuring 30.0 and
36.2µm in diameter; cyst walls are 2.0 and 2.5µm thick.
Mesoepicystal archeopyles are angular in outline andcomprise 66 and 69% of the cysts’ diameters. Wall-forming crystals are radially arranged, longer than wide; distal
crystal tips differ in size, generating an irregular patternon the outer cyst-surface. The inner cyst-surface appears
more regular, formed by equally distributed crystal terminations of similar size. Ultrastructure of wall-forming
crystals is unknown, the assignment to Calciodinellum is

28Streng, Hildebrand-Habel, Willems

therefore only tentative.
Range: Lower Miocene (within interval NN1-NN4) ofHole 747A, Kerguelen Plateau.
Caracomia sp. cf. Caracomia stella Streng et al., 2002
Plate 3, Figures 15, 17, 18
Remarks: These specimens differ from typical cysts of C.
stella Streng et al., 2002 in the absence of pores and of thecharacteristic wall with epitaxially-grown crystals. Moremassive, stem-like crystals are developed instead. Only
occasionally, the epitaxial growth of the wall-forming
crystals is intimated (Plate 3, Figure 15). The lack ofpores as well as the different wall-structure are most probably due to a diagenetic overprint. Caracomia sp. cf. C.
stella is ovoid, less frequently spherical in shape; diameters range from 27.9 to 33.0µm.
Range: Middle Miocene (within interval NN2-NN4) ofHole 747A, Kerguelen Plateau
Caracomia sp. aff. Caracomia stella Streng et al., 2002
Plate 3, Figures 16, 21, 22
Remarks: These cysts are spherical to slightly ovoid inshape. Diameters range from 27.1 to 34.4µm. The
archeopyle is mesoepicystal, polygonal in outline. The
wall is massive, about 3µm thick, built of stem- to wedgeshaped crystals, which are radially arranged. The outercyst-surface is characterised by an irregular pattern of triand quadrangular crystal terminations of variable sizes.
Range: Lower Miocene (within interval NN1-NN4) ofHole 747A, Kerguelen Plateau.
6.3
Specieswithacombinationarcheopyle - epitractal archeopyles
Lebessphaera sp. cf. Lebessphaera urania Meier et al.,
2002
Plate 4, Figure 4
Remarks: These specimens differ from the typical L. urania Meier et al., 2002 in the larger size and a more bumpy
appearance of the outer cyst-surface. The four examined
specimens of L. sp. cf. L. urania are spherical in shapewith a cyst diameter of 45.2 to 56.2µm. Undehisced cysts
show a faint, descending cingular displacement (Plate 4,
Figure 4).
Range: Lower Miocene (NN1) of Hole 761B, Wombat
Plateau.
Lebessphaera? sp.
Plate 4, Figures 7, 8

Remarks: Probably a new species of Lebessphaera,
which is characterised by interfingering crystals withpolylobate crystal tips resembling jigsaw pieces. Two
specimens were found, which are 29.0 and 38.6µm in
diameter. One specimen shows a descending cingular displacement (Plate 4, Figure 7).
Range: Upper Pliocene (NN16) of Hole 761B, Wombat
Plateau.
6.4 Species with unknown archeopyle
type
Gen. et sp. indet. aff. Calciodinellum elongatum(Hildebrand-Habel et al., 1999) Meier et al., 2002
Plate 4, Figure 23
Remarks: The three specimens found are ovoid in shape,
24.4 to 30.4µm wide and about 15% longer than wide.
The 2.5-3µm-thick, single-layered wall is built of massive
calcite rhombohedrons which form a cobblestone-likepattern on the outer cyst-surface. The archeopyle type isunknown, but might possibly be mesoepicystal. Cysts
resemble C. elongatum in size, shape and archeopyle outline, but wall-forming crystals are more similar to
Fuettererella deflandrei. The habit of crystals suggests atangential ultrastructure of the specimens.
Range: Upper Oligocene (NP24 or NP25) of Hole 747A,
Kerguelen Plateau.
Gen. et sp. indet. 1
Plate 4, Figure 20
Remarks: The single cyst of Gen. et sp. indet. 1 is spherical, 37.4µm in diameter, single-layered, and has a relatively thick wall of 6µm. The wall is built of columnar,
radially-oriented crystals of about 1.5µm width. Length ofcrystals equals wall thickness. The outer cyst-surface ischaracterised by an irregular pattern of crystal terminations of different sizes. The inner surface is similar to theouter. An archeopyle is not present. The ultrastructure of
the wall is unknown, probably radial.
Range: Middle Eocene (NP16) of Hole 761B, Wombat
Plateau.
Gen. et sp. indet. 2
Plate 4, Figure 14
Remarks: A single cyst of Gen. et sp. indet. 2 was found.
The specimen is spherical, 50.5µm in diameter and is
striking because of its large, wall-forming crystals.
Individual crystals of the single-layered wall have been
affected by a diagenetic overprint that caused distal, andespecially proximal, growth of crystals resulting in a relatively thick wall. Inner cyst diameter is less than half ofLong-term evolution of calcareous dinoflagellate associations

29

outer cyst diameter. Cyst somewhat resembles Pirumellaloeblichii (Bolli, 1974) Lentin & Williams, 1993.

Pirumella sp.1
Plate 4, Figures 12, 15

Range: Upper Paleocene (NP9) of Hole 761B, Wombat
Plateau.

Remarks: The three specimens of Pirumella sp.1 are
ovoid in shape with a length/width ratio of about 1:0.88;
the largest specimen measures 56.3µm in length, smallest
47.1µm. The double-layered wall consists of a thin inner
layer (about 1µm thick) and a thick outer layer of about
6µm. The outer layer is built of massive, interlocking andintertwining, bar-like crystals which produce a rough distal cyst-surface. The inner layer is principally similar toouter, but crystals of the inner layer are much smaller andless elongated. Crystals of both layers obliquely oriented.
No archeopyle was observed.

Gen. et sp. indet. 3
Plate 4, Figures 16, 17
Remarks: Cysts of Gen. et sp. indet. 3 are spherical andsingle-layered, and have obviously been influenced bydiagenetic overgrowth obscuring the primary crystal
habit. All cysts appear somewhat spiny due to secondary
growth of distal crystal-tips. No archeopyle or archeopyle suture is visible in any of the cysts. Sizes of cysts range
from 30.8 to 64.3µm. Ultrastructure of wall unknown.
Range: Lower Paleocene (NP3), Upper Paleocene (NP5)and Lower Miocene (NN1) of Hole 761B, Wombat
Plateau.
Orthopithonella? sp. cf. Orthopithonella? minuta
Fütterer, 1990
Plate 5, Figures 15-17
Remarks: The problematic nature of O.? minuta has been
extensively discussed by Streng et al. (in press). No distinct archeopyle type can be assigned to O.? minuta,
because the preserved archeopyles generally have an
irregular and variable outline that admit no reliableassignment of involved plates.
Tentatively assigned to O.? minuta are several specimens from Hole 761B, and some from Hole 747A, thatclosely resemble the type material of Fütterer (1990).
They are spherical and variable in size; cyst diameters
range from 23.7 to 50.6µm (mean = 33.1µm, n = 104).
The single-layered wall is built of short and sturdy crystals which are approximately as wide as long (about2µm). The outer cyst-surface is characterised by an irregular pattern of trigonal to polygonal crystal terminations.
Archeopyles are generally relatively large, circular toirregularly circular in outline, most likely involving morethan one plate. However, smaller angular archeopyles areobserved as well, which are probably the result of walldamage and not related to an archeopyle. Occasionally, anarcheopyle suture and a accentuated operculum are visible in undehisced cysts (Plate 5, Figure 17), most undehisced cysts show no excystment features, though. Due tothe poor definition and variability of this morphotype,probably more than one species is united within O.? sp.
cf. O.? minuta.
Range: Lower and Upper Paleocene (NP3 or NP4, NP6,
NP9) and Middle Eocene (NP14 to NP16) of Hole 761B,
Wombat Plateau, and Paleocene-Eocene transition (within interval NP11-NP13) and Lower Miocene (withininterval NN1-NN4) of Hole 747A, Kerguelen Plateau.

Range: Lower Eocene (within interval NP11-NP13) ofHole 747A, Kerguelen Plateau.
Pirumella sp.2
Plate 4, Figures 9, 10
Remarks: Cysts of Pirumella sp.2 are spherical, measure31.7 to 49.2µm in diameter (mean = 39.0µm, n = 26) andhave a single-layered 4-5µm-thick wall. Wall built of
obliquely-oriented, plate-like crystals of different sizes,
smaller crystals fill the gaps between the larger ones.
Distal cyst-surface rough, dominated by several large
crystal terminations, which appear bar-like. Pattern ofproximal surface similar to distal, but with a smoothertexture. Ultrastructure of wall interpreted as oblique.
None of the specimens exhibits an archeopyle.
Range: Upper Paleocene (NP9) of Hole 761B, Wombat
Plateau.
Pirumella sp.3
Plate 4, Figures 21, 22
Remarks: A single spherical cyst of Pirumella sp.3 wasobserved. It measures 30.2µm in diameter and its wall is
2.7µm thick. The wall is interpreted as single-layered,although it is obviously constructed of a double row of
obliquely-oriented crystallites. Crystals of the basal, proximal row appear smaller and elongated in contrast to thoseof the distal row that have a more blocky shape. However,crystals of the proximal row also protrude into the distal
row and vice versa. Therefore, no partition into two discrete ‘layers’ is possible. The inner surface is characterised by an irregular pattern of polygonal (about 1µm in
diameter) and elongated polygonal (up to 2.5µm in
length) crystal-faces. Outer surface typically has irregularly-arranged crystal terminations of uniform size (about2µm) and appears coarser and less smooth than the innersurface. No archeopyle is visible.
Range: Middle Eocene (NP15 or NP16) of Hole 761B.
Wombat Plateau.

30

Streng, Hildebrand-Habel, Willems‘Rhabdothorax’ spp.
Plate 4, Figure 19
Remarks: The generic name Rhabdothorax was introduced by Kamptner (1958) for typically ovoid, but also
spherical, tests, built of flat, polygonal crystallites distally bearing a central spine which may be capitate.
However, Kamptner (1958) failed to give a Latin diagnosis to make his new genus available. A Latin diagnosis
was later provided by Gaarder & Heimdal (1973, p.97)
who thereby validated the genus (Rhabdothorax
Kamptner ex Gaarder & Heimdal, 1973). Subsequently,
many authors included various types of spiny cysts ofuncertain affinity in Rhabdothorax using open nomenclature (e.g. Keupp & Kowalski, 1992; Keupp & Kohring,
1993; Kienel, 1994). Recently, Janofske (2000) emended
the species belonging to Rhabdothorax, i.e. R. regale(Gaarder, 1954) Gaarder in Gaarder & Heimdal, 1973
(senior synonym of R. gerenus Kamptner, 1967) and R.
erinaceus (Kamptner, 1937) Kamptner, 1958, and concluded that Rhabdothorax is a junior synonym of
Scrippsiella Balech ex Loeblich, 1965, since the type of
Rhabdothorax, R. erinaceus, is a junior synonym of
Scrippsiella trochoidea (von Stein, 1883) Loeblich, 1965
emend. Janofske, 2000. R. regale was newly combined to
become Scrippsiella regalis (Gaarder, 1954) Janofske,
2000. Consequently, the genus Rhabdothorax became
obsolete. Accordingly, all morphotypes of Rhabdothorax
published under open nomenclature should now bereferred to as Scrippsiella spp. However, since
Scrippsiella is characterised by a tangential ultrastructure(see Janofske, 2000), and some of the specimens published as Rhabdothorax sp. were proven to have a radial
wall-type (Hildebrand-Habel & Streng, 2003) and additionally show morphological differences, an accommodation of those specimens within Scrippsiella is problematic. Therefore, we retain the name ‘Rhabdothorax’ as an
informal name to unite more-or-less spiny cysts of uncertain affinity.
Range: Campanian (within interval CC22-CC24), Upper
Maastrichtian (CC26), Middle Eocene (NP14 to NP16)
and Lower Miocene (NN1) of Hole 761B, Wombat
Plateau, and Upper Oligocene to Lower Miocene (withininterval NN24-NP2) of Hole 747A, Kerguelen Plateau.
Thoracosphaera? prolata Bukry & Bramlette, 1969
Plate 5, Figures 1-12
1969 Thoracosphaera prolata Bukry & Bramlette, p.141,
pl.3, fig.18.
1975 Thoracosphaera prolata Bukry & Bramlette: Jafar,
p.82, pl.14, fig.5.
?1979 Thoracosphaera prolata Bukry & Bramlette:
Müller, pl.5, fig.11.
1985 Thoracosphaera prolata Bukry & Bramlette: PerchNielsen, fig.75.3?1992 Thoracosphaera prolata Bukry & Bramlette:
Siesser & Bralower, pl.4, fig.12.
?1999 Sphaerodinella? tuberosa forma elongata
Hildebrand-Habel et al., p.83, pl.5, figs 5-7.
Remarks: T.? prolata was first described by Bukry &Bramlette (1969) from Middle Eocene sediments of thethree major oceans and some additional locations. The
species was defined as being extremely eccentric with alength/width ratio exceeding 2.0 and an outer surface“with a distinctly sculptured appearance” (Bukry &Bramlette, 1969, p.141). Since Bukry & Bramlette (1969)
used light-microscopic methods, they did not provide
additional information on archeopyle characteristics orhabit of individual, wall-forming crystals. Additionally,
they reported less elongate forms associated with T.? prolata. Subsequently, T.? prolata has been reported from theLower Eocene (Müller, 1979; Steinmetz & Stradner,
1984), Middle Eocene (Bukry, 1971; Shafik, 1975; Jafar,1979), Middle Eocene to Lower Oligocene (Siesser &Bralower, 1992), Middle Miocene (Bukry, 1973), andUpper Miocene (Jafar, 1975) of the three major oceans.
Unfortunately, only Jafar (1975), Müller (1979) and
Siesser & Bralower (1992) provided illustrations of theirmaterial, and only the depicted specimen of Jafar (1975)
corresponds to the definition of Bukry & Bramlette(1969). More recently, Hildebrand-Habel et al. (1999)
described a morphotype, which is similar to T.? prolata,as Sphaerodinella? tuberosa forma elongata from theMiddle Eocene of the South Atlantic. They reported
length/width ratios of 1.1 to 1.8 and homologised thearcheopyle, although irregular in outline, with the plates
2’-4’ and 1a-3a. Recently, Meier et al. (2002) discovered
ovoid cysts from surface sediments and water samples ofthe Mediterranean Sea, which they interpreted as being
identical with the morphotype of Hildebrand-Habel et al.
(1999) and therefore established the new combination
Calciodinellum elongatum, giving the form ofHildebrand-Habel et al. (1999) species rank. Additionally,
they considered T.? prolata not to be synonymous with C.
elongatum because of the high length/width ratio of T.?
prolata. The specimens from the Quaternary of theMediterranean Sea only show length-width ratios of 1.1 to
1.2 (K.J.S. Meier, pers. comm., 2003).
Many specimens were found in Holes 747A and 761B
that resemble T.? prolata of Bukry & Bramlette (1969),
especially in the Middle Eocene of Hole 761B. As alreadymentioned by Bukry & Bramlette (1969), less ovoid specimens also co-occur with extremely elongated morphotypes in Hole 761B. However, the restricted definition of
Bukry & Bramlette (1969) concerning the length/width
ratio of T.? prolata (>2.0) is not reproducible with thematerial at hand. Examinations of the length/width ratios
in the available material yielded values of 1.0 to 2.4. The
frequency distribution of these values allows a distinction
into two groups (Figure 7). The first group shows lengthwidth ratios of 1.0 to 1.7 and the second group of 1.9 toLong-term evolution of calcareous dinoflagellate associations

2.4. The specimens of both groups show the same morphological characteristics, besides the shape, though: apattern of triradiate crystal-tops on the outer cyst-surface,a single-layered wall, and an apically-located archeopyleof indeterminable type. Therefore, the two morphotypes
can only be distinguished by the shape. Specimens
belonging to the first group most probably correspond to
the specimens described by Hildebrand-Habel et al.
(1999) as S.? tuberosa forma elongata, which would inturn mean that they are conspecific with C. elongatum.
However, since in none of the observed specimens is anunequivocal outline of the archeopyle discernible, we
refer to those specimens as T.? prolata sensu lato. The
specimens depicted by Müller (1979) and Siesser &Bralower (1992) most likely belong to this group, too.
Concomitantly, specimens with length/width ratios of>1.8 are referred to as T.? prolata sensu stricto, extending
the definition of Bukry & Bramlette (1969). As long as
the archeopyle characteristics of T.? prolata have notunambiguously been proven, it remains dubious if T.?
prolata is the senior synonym of C. elongatum, or if thespecimens described by Meier et al. (2002) from theMediterranean Sea represent a separate species. Since thearcheopyle outline of T.? prolata does not allow an accurate designation of the plate or plates involved, no appropriate genus can be assigned to T.? prolata. A genericreallocation, as already proposed by Fütterer (1976), however, is necessary because Thoracosphaera is currently
regarded as a monospecific genus due to its unique lifecycle (Tangen et al., 1982; Fensome et al., 1993).

31

and a re-examination of a sample from the type material
yielded no specimens of T.? prolata.
Range: Upper Paleocene (NP9) and Middle Eocene ofHole 761B (NP14 to NP16), Wombat Plateau, andPaleocene-Eocene transition (within interval NP11NP13) of Hole 747A, Kerguelen Plateau.
6.5 Pithonelloid species with a circular
aperture
Pithonella sp.
Plate 2, Figure 18
Remarks: The single, spherical to slightly ovoid specimen of Pithonella sp. has a maximum diameter of 41µm
and has obviously been diagenetically altered. The wallforming crystals show a secondary overgrowth resulting
in an oversized appearance. Nevertheless, the typical spiral pithonelloid arrangement of the crystals is still visible,
which permits a generic determination.
Range: Campanian (within interval CC22-CC24) of Hole
761B, Wombat Plateau.
Acknowledgements
This research used samples provided by the Ocean Drilling
Program (ODP). ODP is sponsored by the US National Science
Foundation (NSF) and participating countries under management of Joint Oceanographic Institutes (JOI), Inc. The Scripps
Institute of Oceanography is acknowledged for the provision of
the type material of Thoracosphaera? prolata. Financial support
for this study came from a grant of the ‘City of Bremen’ to MS.
Constructive review comments on this paper by H. Keupp and
J.A. Lees were much appreciated.

References

Figure 7: Frequency distribution of the length/width ratio of the problematic species Thoracosphaera? prolata. See text for further explanations

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AMPH 116P, 488cm) was performed. Unfortunately, theresidual type material underwent considerable carbonate
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Long-term evolution of calcareous dinoflagellate associations

35

Plate 1

1: Fuettererella deflandrei (Kamptner, 1956) Hildebrand-Habel & Streng, in press (cyst 122-5H-5/X17); Middle
Miocene.
2: Fuettererella tesserula (Fütterer, 1977) Kohring, 1993 (cyst 122-8H-3/XIII14), specimen with secondary aperture;
Middle Eocene.
3: Fuettererella belliata Streng et al., in press (cyst 120-19X-2-11/IV2); Early Eocene.
4: Fuettererella elliptica Kohring, 1993 (cyst 120-19X-2-11/XIII12); Early Eocene.
5: Fuettererella? sp. aff. Calciodinellum sp.1 (cyst 122-4H-1/XIII9); Late Pliocene.
6: Calcicarpinum tetramurum Kienel, 1994 (cyst 120-20X-1/VI9); Early Paleocene.
7: Cervisiella saxea (Stradner, 1961) Hildebrand-Habel et al., 1999 (122-8H-3/V14); Middle Eocene.
8: Cervisiella operculata (Bramlette & Martini, 1964) Streng et al., in press (cyst 122-16X-2/IX3-2); Late Paleocene.
9: Cervisiella sp. aff. Operculodinella reticulata Kienel, 1994 (cyst 120-19X-2-139/I40); Late Paleocene.
10, 12, 13, 15: Orthopithonella? sp. aff. Orthopithonella gustafsonii (Bolli, 1974) Streng et al., 2002 (cysts 122-18X2/IV2, 120-20X-1/V45, 120-20X-1/VI35, 120-21X-1/X38); Late Paleocene (10), Early Paleocene (12,13), Early Maastrichtian (15); see also Plate 2, Figure 9.
11: Cervisiella? sp. aff. Cervisiella saxea (Stradner, 1961) Hildebrand-Habel et al., 1999 (cyst 122-5H-5/V25-2);
Middle Miocene.
14: Leonella granifera (Fütterer, 1977) Janofske & Karwath in Karwath, 2000 (cyst 122-4H-1/XIII18); Late Pliocene.
16: Pirumella edgarii (Bolli, 1974) Lentin & Williams, 1993 (cyst 120-7H-4/V1); Middle Miocene; see also Plate 2,
Figure 4.
17: Pirumella sp. aff. Pirumella thayeri (Bolli, 1974) Lentin & Williams, 1993 (cyst 120-4H-3/XIII10-2); Early
Pliocene.
18, 22: Fuettererella flora (Fütterer, 1990) Hildebrand-Habel & Streng, in press (cysts 120-20X-1/VIII11, 120-19X-211/V24); Early Paleocene and Early Eocene; see also Plate 2, Figure 6.
19: Pirumella parva (Fütterer, 1984) Lentin & Williams, 1993 (cyst 122-16X-2/VI9-2); Late Paleocene; see also Plate
2, Figures 10, 13.
20: Pirumella multistrata (Pflaumann & Krasheninnikov, 1978) Lentin & Williams, 1993 (cyst 122-23X-3/99); Late
Maastrichtian.
21: Gen. et sp. indet. aff. Pirumella williambensonii (Bolli, 1978) Williams et al., 1998 (cyst 122-25X-3/58), specimen
with secondary aperture; Campanian; see also Plate 2, Figure 7.
23: Orthopithonella? congruens Fütterer, 1990 (cyst 122-21X-6/05); Late Maastrichtian.
24: Orthopithonella? sp. aff. Orthopithonella? globosa (Fütterer, 1984) Lentin & Williams, 1985 (cyst 120-14H-5/V202), specimen with secondarily enlarged archeopyle; Late Oligocene; see also Plate 2, Figure 2.

36Streng, Hildebrand-Habel, Willems

Plate 1 cont’d

25: Gen. et sp. indet. aff. Tetramerosphaera lacrimula Willems, 1985 (cyst 122-21X-2/13); Early Paleocene; see also
Plate 2, Figure 15.
26: Pirumella krasheninnikovii (Bolli, 1974) Lentin & Williams, 1993 (cyst 120-21X-1/II4); Early Maastrichtian; seealso Plate 2, Figure 3.
27: Orthopithonella? aequilamellata Willems, 1988 (cyst 120-19X-2-139/V6); Late Paleocene; see also Plate 2, Figure
1.
28: Pirumella? sp. aff. Pirumella amplicrystallina (Pflaumann & Krasheninnikov, 1978) Lentin & Williams, 1985 (cyst122-22X-3/IX3-2); Late Maastrichtian; see also Plate 2, Figure 12.
29: Orthopithonella? sp. (cyst 122-14X-3/X21); Middle Eocene; see also Plate 2, Figure 8.
30: Orthopithonella? globosa (Fütterer, 1984) Lentin & Williams, 1985 (cyst 120-21X-1/IX1); Early Maastrichtian; seealso Plate 2, Figures 11, 14.

Long-term evolution of calcareous dinoflagellate associations

Plate 1
Species with an apical archeopyle that involves plate 3’ only
Scale-bar = 10µm, except for 22 and 25-30 (= 20µm)
1, 2, 5, 7, 8, 10, 11, 14, 19-21, 23, 25, 29 = ODP Leg 122, Hole 761B, Wombat Plateau
3, 4, 6, 9, 12, 13, 15-18, 22, 24, 26-28, 30 = ODP Leg 120, Hole 747A, Kerguelen Plateau

37

38

Streng, Hildebrand-Habel, Willems

Plate 2

1: Orthopithonella? aequilamellata Willems, 1988 (cyst 120-19X-2-139/V4); Late Paleocene.
2: Orthopithonella? sp. aff. Orthopithonella? globosa (Fütterer, 1984) Lentin & Williams, 1985 (cyst 120-12H2/VII26-2); Early Miocene.
3: Pirumella krasheninnikovii (Bolli, 1974) Lentin & Williams, 1993 (cyst 120-21X-1/XI12); Early Maastrichtian.
4: Pirumella edgarii (Bolli, 1974) Lentin & Williams, 1993 (cyst 120-12H-2/VII8-2); Early Miocene.
5: Ruegenia inaequilamellata Willems, 1992 (cyst 120-20X-1/IX11); Early Paleocene.
6: Fuettererella flora (Fütterer, 1990) Hildebrand-Habel & Streng, in press (cyst 120-19X-2-11/V2); Early Eocene.
7: Gen. et sp. indet. aff. Pirumella williambensonii (Bolli, 1978) Williams et al., 1998 (cyst 122-25X-3/58);
Campanian.
8: Orthopithonella? sp. (cyst 122-14X-3/XIV14); Late Oligocene.
9: Orthopithonella? sp. (cyst 120-21X-1/X3); Early Maastrichtian.
10, 13: Pirumella parva (Fütterer, 1984) Lentin & Williams, 1993 (cysts 120-19X-2-11/V31, 122-16X-2/V5-2); Early
Eocene and Late Paleocene.
11, 14: Orthopithonella? globosa (Fütterer, 1984) Lentin & Williams, 1985 (cysts 120-21X-1/IX2, 122-22X-3/X10-2);
Early and Late Maastrichtian.
12: Pirumella? sp. aff. P. amplicrystallina (Pflaumann & Krasheninnikov, 1978) Lentin & Williams, 1985 (cyst 12222X-3/IV7-2); Late Maastrichtian.
15: Gen. et sp. indet. aff. Tetramerosphaera lacrimula Willems, 1985 (cyst 122-21X-2/13); Early Paleocene.
16: Pithonella sphaerica (Kaufmann in Heer, 1865) Zügel, 1994 (cyst 120-21X-1/XI5); Early Maastrichtian.
17: Lentodinella danica Kienel, 1994 (cyst 122-21X-6/74); Late Maastrichtian.
18: Pithonella sp. (cyst 122-25X-3/31); Campanian.

Long-term evolution of calcareous dinoflagellate associations

Plate 2
Cross-sections of cyst walls and surface pattern of various cysts and pithonelloid species
Scale-bar = 5µm, except for 11 and 16-18 (= 10µm)
1-6, 9-11, 16 = ODP Leg 120, Hole 747A, Kerguelen Plateau
7, 8, 12-15, 17, 18 = ODP Leg 122, Hole 761B, Wombat Plateau

39

40

Streng, Hildebrand-Habel, Willems

Plate 3

1: Calciodinellum albatrosianum (Kamptner, 1963) Janofske & Karwath in Karwath, 2000 (cyst 122-2H-3/VI14);
Quaternary.
2: Calciodinellum operosum Deflandre, 1947 (cyst 120-14H-2/V6-2); Early Miocene.
3: Calciodinellum levantinum Meier et al., 2002 (cyst 122-2H-3/X18); Quaternary.
4: Calciodinellum sp.2 (cyst 120-12H-2/IX12-2); Early Miocene.
5: Calciodinellum elongatum (Hildebrand-Habel et al., 1999) Meier et al., 2002 (cyst 122-2H-3/VI18); Quaternary.
6-9: Calciodinellum sp.1 (cysts 122-4H-1/XIV5, 122-4H-1/IV18, 122-4H-1/VI8); Late Pliocene.
10: Calciodinellum clamosum subsp. clamosum Streng et al., in press (cyst 120-20X-1/VIII3); Early Paleocene.
11: Calciodinellum clamosum subsp. latum Streng et al., in press (cyst 122-18X-2/IV13); Late Paleocene.
12: Calciodinellum kerguelense Streng et al., in press (cyst 120-6H-1/V19); Late Miocene.
13: Calciodinellum sp. cf. C. operosum Deflandre, 1947 (cyst 122-7H-4/IV7); Early Miocene.
14: Caracomia stella Streng et al., 2002 (cyst 122-5H-5/ss2); Middle Miocene.
15, 17, 18: Caracomia sp. cf. C. stella Streng et al., 2002 (cysts 120-9H-5/VI18, 120-9H-5/V32, 120-9H-5/VIII4);
Middle Miocene.
16, 21, 22: Caracomia sp. aff. C. stella Streng et al., 2002 (cysts 120-12H-2/VII23-2, 120-12H-2/V7); Early Miocene.
19: Scrippsiella regalis (Gaarder, 1954) Janofske, 2000 (cyst 122-2H-3/IX2), slightly compressed specimen;
Quaternary.
20: Caracomia arctica (Gilbert & Clark, 1983) Streng et al., 2002 (cyst 120-3H-3/X9); Late Pliocene.

Long-term evolution of calcareous dinoflagellate associations

Plate 3Species with a mesoepicystal archeopyle
Scale-bar = 10µm for whole cysts and 3µm for details (9, 15, 21, 22)
1, 3, 5-9, 11, 13, 14, 19 = ODP Leg 122, Hole 761B, Wombat Plateau
2, 4, 10, 12, 15-18, 20-22 = ODP Leg 120, Site 747, Kerguelen Plateau

41

42

Streng, Hildebrand-Habel, Willems

Plate 4

1: Pernambugia tuberosa (Kamptner, 1963) Janofske & Karwath in Karwath, 2000 (cyst 122-7H-4/X8), showing
archeopyle suture; Early Miocene.
2, 3: Pernambugia? patata Streng et al., in press (cysts 120-1R-4/VI8-3, 120-1R-4/IX7-3); Early Oligocene.
4: Lebessphaera sp. cf. L. urania Meier et al., 2002 (cyst 122-7H-4/VI18), oblique ventral view showing faintarcheopyle suture and descending cingular displacement; Early Miocene.
5, 6: Lebessphaera urania Meier et al., 2002 (cysts 120-14H-5/VI9-2, 120-14H-2/X32); Late Oligocene and Early
Miocene.
7, 8: Lebessphaera sp. (cyst 122-4H-1/IV8), 7, ventral view with descending cingular displacement, 8, detail of outersurface of cyst showing polylobate crystal terminations; Late Pliocene.
9, 10: Pirumella sp.2 (cysts 122-16X-2/XI8-2, 122-16X-2/VII2-2); Late Paleocene.
11: Pirumella strobila (Keupp, 1979) Lentin & Williams, 1993 (cyst 122-21X-6/40); Late Maastrichtian.
12, 15: Pirumella sp.1 (cyst 120-19X-2-11/VI18); Early Eocene.
13: Orthotabulata obscura Kienel, 1994 (cyst 122-21X-2/07); Early Paleocene.
14: Gen. et sp. indet. 2 (cyst 122-16X-2/VII5-2); Late Paleocene.
16, 17: Gen. et sp. indet. 3 (cysts 122-7H-4/IV6, 122-7H-4/VII25); Early Miocene.
18: Pirumella spinosa (Keupp, 1979) Lentin & Williams, 1993 (cyst 122-21X-6/09); Late Maastrichtian.
19: ‘Rhabdothorax’ sp. with relatively large circular archeopyle (cysts 120-14H-2/II3-2); Early Miocene.
20: Gen. et sp. indet. 1 (cyst 122-8H-3/VII12); Middle Eocene.
21, 22: Pirumella sp.3 with pseudo double-layered wall (22) (cyst 122-9H-5/X1-2); Middle Eocene.
23: Gen. et sp. indet. aff. Calciodinellum elongatum (Hildebrand-Habel et al., 1999) Meier et al., 2002 (cyst 120-14H5/VI31); Late Oligocene.

Long-term evolution of calcareous dinoflagellate associations

Plate 4
Species with an epitractal archeopyle (1-8) and with unknown archeopyle type (9-23)
Scale-bar = 10µm, except 8, 9, 22 (= 3µm) and 12 (= 6µm)
1, 4, 7-11, 13, 14, 16-18, 20-22 = ODP Leg 122, Hole 761B, Wombat Plateau
2, 3, 5, 6, 12, 15, 19, 23 = ODP Leg 120, Hole 747A, Kerguelen Plateau

43

44

Streng, Hildebrand-Habel, Willems

Plate 5

1-5: Thoracosphaera? prolata Bukry & Bramlette, 1969 sensu stricto, meaning cysts with length/width ratio >1.8; 13, undehisced cysts (cysts 122-8H-3/VI25, 122-8H-3/VII2, 122-8H-3/XII3), 4, apical view of dehisced specimen
showing archeopyle outline (cyst 122-8H-3/A6), 5, lateral view of dehisced specimen (cyst 122-8H-3/IX10);
Middle Eocene.
6-12: Thoracosphaera? prolata Bukry & Bramlette, 1969 sensu lato, meaning cysts with length/width ratio <1.8; 6-9,
12, undehisced specimens with varying outline (cysts 122-8H-3/X8, 122-8H-3/IV1, 122-8H-3/VII8, 122-8H3/VIII10, 122-8H-3/IX6), 10, 11, lateral view of dehisced specimens (cysts 122-8H-3/VIII6, 122-8H-3/XIV6);
Middle Eocene.
13, 14: Thoracosphaera heimii (Lohmann, 1920) Kamptner, 1944 (cysts 122-4H-1/S1, 122-5H-5/IV1), two specimens
showing subcircular apertures; Late Pliocene and Middle Miocene.
15-17: Orthopithonella? sp. cf. O.? minuta Fütterer, 1990; 15, oblique apical view with irregular archeopyle outline(cyst 122-9H-5/V3-2), 16, undehisced cyst (cyst 122-9H-5/II3-2), 17, undehisced cyst showing archeopyle
suture (cyst 122-9H-5/I1-2); Middle Eocene.

Long-term evolution of calcareous dinoflagellate associations

45

Plate 5
Variability of the problematic taxa Thoracosphaera? prolata Bukry & Bramlette, 1969 (1-12) and Orthopithonella? sp. cf. O.?
minuta Fütterer, 1990 (15-17), as well as the coccoid stage of Thoracosphaera heimii (Lohmann, 1920) Kamptner, 1944 (1314)
Scale-bar = 10µm. All ODP Leg 122, Site 761, Wombat Plateau

46

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Announcement of INA CD-ROM Version 2 releaseby Sherwood W. Wise, Jr. (INA President)
The INA is pleased to announce the release of Version 2(2003.1.2) of its CD-ROM Series No.1, entitled‘Electronic Calcareous Nannofossils’. Like the previous
version, issued last year, this release is limited to 50
copies. In addition to the interactive digital-image catalogue of over 600 Cenozoic species, this version contains‘The Complete Taxonomic Index of Calcareous
Nannoplankton’ (1966 to present). Included in a searchable MS Excel format are the taxonomic indexes of Alfred
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van Heck (1979-82), John C. Steinmetz (1983-89),
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Also new in v.2 is ‘The Best of the INA Website’, which
includes a wealth of information about calcareous nannoplankton, compiled by our INA Website Editor, Jeremy
Young. We continue to provide electronic reprints of ODP
nannofossil papers and several other major MesozoicCenozoic nannoplankton bibliographies and databases. A
major goal of this publication has been to make theseresources available to INA members and othermicropalaeontologists at an affordable price. We have notraised the price of v.2 of this CD, despite having added
considerably to its contents. All proceeds from the sale ofthis product go to the INA. Purchasers of v.1 of the CD
will receive a free upgrade.
Ordering information
INA CD-ROM Ser. No.1 v.2 can be ordered from either
the INA Treasurer, Stacia Spaulding (jrice@ludl.tds.net),or from the UK Assistant Treasurer, Matt Hampton(100710.1020@compuserve.com).
Cost
US$100 for INA members, US$140 for non-members,
US$200 for academic institutions and libraries, government agencies, and industry consultants, and US$3000 for
non-sponsor corporate industry users (for distribution on
any five computers; for a site license for unlimited use,
US$5000).
Contents
Electronic Calcareous Nannofossils„, INA CD-ROM Ser.
No.1, v.2 (2003.1.2) contains the following programs,
databases and indexes, compiled by Sherwood W. Wise,
Jr., J. Mitch Covington, Bryan C. Ladner and WuchangWei:
1. The NannoWare„/BugCam„ package is an interactive, icon-driven digital-image catalogue of over 600
Cenozoic calcareous nannofossil taxa, designed to assist
the investigator working at the microscope with limited
literature resources, comprising: the NannoWare„ database v.2002.9.1, authored by Sherwood W. Wise, Jr(FSU), Laurel M. Bybell (USGS), J. Mitchener
Covington (BugWare, Inc.), Eric de Kaenel (U. of

Neuchatel), Bryan C. Ladner (FSU), Patricia Marino(Bari U.), Kristeen L. McGonigal (FSU), Darren D.
Millman (FSU), Jay P. Muza (Broward CC, FL), James J.
Pospichal (FSU/BugWare, Inc), Jean Self-Trail (USGS),
Katharina von Salis (ETH), Giuliana Villa (U. Parma) and
Wuchang Wei (FSU), 2002, assisted by Jinfen Li,
Floranda Thomas and David Davenport (graphic design
and jacket layout) at FSU; BugCam„ v.2002.9.2, a proprietary software program written by J. Mitch Covington(BugWare, Inc.), 2002.
2. The Complete Taxonomic Index of Calcareous
Nannoplankton in MS Excel format in three files, comprising: Alfred R. Loeblich, Jr. and Helen Tappan Parts I,
II, and III, with coccoliths and calcispheres combined(1966-1969 from Phycologia, Journal of Paleontology);
Alfred R. Loeblich, Jr. and Helen Tappan IV to VII withcoccoliths and calcispheres combined (1970-1973 from
Journal of Paleontology); Shirley E. van Heck (1979-82),
John C. Steinmetz (1983-89) and William G. Siesser(1990-2002), with coccoliths and calcispheres in separate
files, derived from the INA Newsletter and Journal of
Nannoplankton Research.
3. Calcareous nannoplankton bibliographies, comprising: MS Word INA Bibliographies (1990-2002 from the
Journal of Nannoplankton Research) by William G.
Siesser; MS Access Cenozoic and Mesozoic bibliographies by Laurel M. Bybell; MS Excel and MS Word
Cenozoic and Mesozoic bibliographies by Wuchang Wei(sorted by author and year).
4. Two additional databases by Laurel Bybell, migrated
from D-BASE to MS Access by Bryan C. Ladner, providing: Cenozoic and Mesozoic nannofossil taxa with synonymies; catalogue and citations of calcareous nannofossils illustrations.
5. Electronic reprints of calcareous nannofossil papers
in PDF format, compiled by Wuchang Wei. These aremostly from the open literature, particularly the Ocean
Drilling Project Scientific Research volumes.
6. The best of the INA website (http://www.nhm.ac.uk/
hosted_sites/ina/index.html) compiled by Jeremy Young.
7. Introduction to NannoWare/BugCam in a Power
Point slide show by Mitch Covington.
Feedback
We would like your input. Please send corrections and/or
suggestions for the CD to our list server atnannoware@lists.fsu.edu or to the first compiler,
Sherwood W. Wise, Jr. (wise@gly.fsu.edu).

© 2002, International Nannoplankton Association, Inc.